algae

hi . i am posting this for a friend , the problem is his pond water is crystal clear when you check it with a glass he as all the equipment uv filters the big massive bath tub filtration system , the works i mean its the bees knees lol. but when looking in his pond it appears mucky but like i say the water is crystal clear in a glass , he tells me that he brushes the liner to try to get rid of the green algea off it but keeps coming back, he as a bamboo roof to keep the sun off aswell , have you guys got any suggestions? , he would be very bratefull as he seems to be running out of ideas as to what it can be , cheers in advance , chris.

 

any ideas anyone?

 

does he have Koi

 

yes he does aswell as sturgeon and goldies plus some tench and possibly some others as i say its his and i am only trying to help him

 

I would say fish poo is the problem too many fish for the filter or that could do with a good clean out which they all need periodically to keep them working well I would also suggest to him to do PH test of the water and then check if thats ok ? , quick fix is to to do regular water changes ie take out a 1/4 and replace with fresh

we have someone on here who keep KOI and would know more than me mmm forgotten who it is